var user = {
  name: '李逵',
  birth: '2006-9-6'
}
observe(user)
function showFristName() {
  document.querySelector('#firstName').textContent = '姓: ' + user.name[0]
}
function showLastName() {
  document.querySelector('#lastName').textContent = '名: ' + user.name[1]
}

autorun(showFristName)
autorun(showLastName)
// window.__fun = showFristName
// showFristName()
// window.__fun = null
user.name='老旧'